Key Laboratory of Maricultural Organism Disease Control, Ministry of Agriculture and Rural Affairs, Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, P. R. China.
Qingdao Aquarium, Qingdao, 266003, P. R. China.
J Microbiol. 2019 Sep;57(9):759-768. doi: 10.1007/s12275-019-9175-7. Epub 2019 Aug 3.
The cultivation of microbial species remains a primary challenge in microbiology and obtaining pure cultures is essential for the study of microbial physiology and function. When isolating microorganisms from aquaculture environments, Vibrio are the most dominate isolates on the media that are commonly used. In order to expand our ability to study microbial species, an easy-operation and low-cost medium that can reduce the interference of Vibrio strains and increase the cultivability of other bacteria is urgently needed. We compared viable cell counts on conventional media (CM; including Marine Agar 2216 and LB media) and diluted media (DM; including 1/10-Marine Agar 2216, 1/10-LB). We also assessed the diversity of cultivable microorganisms under high and low nutrient conditions by a plate-wash strategy coupled with high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene. The results show that microbial communities from DM, especially 1/10-Marine Agar 2216, are more diverse than those obtained from CM. Vibrio isolates were reduced on DM. PICRUSt analysis revealed that nutrient composition is a significant contributor to the diversity and function of the cultivable microbial communities. Bacteria grown on CM possess more pathogenic characteristics, whereas DM favors the growth of bacteria that have multiple metabolic functions. Collectively, our data provide strong evidence that dilution of CM influences the cultivability of bacteria from aquaculture seawater. It also supports that DM can expand the range of microbial species that can be cultivated. This study also provides insights for media design in microbial cultivation from aquaculture systems.
从水产养殖环境中分离微生物时，弧菌是最常见的优势菌属，通常在常用的培养基上分离。为了拓展我们对微生物物种的研究能力，我们迫切需要一种操作简单、成本低廉的培养基，它可以减少弧菌菌株的干扰，提高其他细菌的可培养性。我们比较了传统培养基（CM，包括 Marine Agar 2216 和 LB 培养基）和稀释培养基（DM，包括 1/10 Marine Agar 2216、1/10 LB）上的活菌计数。我们还通过平板洗涤策略结合 16S rRNA 基因 V4 高变区的高通量测序，评估了高营养和低营养条件下可培养微生物的多样性。结果表明，DM 中的微生物群落，特别是 1/10 Marine Agar 2216，比 CM 中的更具多样性。DM 上的弧菌分离株减少。PICRUSt 分析表明，营养成分是可培养微生物群落多样性和功能的重要贡献者。在 CM 上生长的细菌具有更多的致病性特征，而 DM 则有利于具有多种代谢功能的细菌生长。总之，我们的数据有力地证明了 CM 的稀释会影响水产养殖海水中细菌的可培养性。它还支持 DM 可以扩大可培养微生物物种的范围。这项研究还为水产养殖系统中微生物培养的培养基设计提供了思路。
